Tetralogy of Fallot.

The optimal surgical approach and timing for patients with tetralogy of Fallot remain controversial. There are two options in current practice: a two-stage repair (an initial palliative aortopulmonary shunt at an early age followed by complete repair at an older age) or primary complete repair. There has been a trend towards primary repair at a young age, which can be attributed to advances in anesthetic and cardiac surgical techniques. Primary repair has several advantages. The correction can be done in one operation and shunt complications are avoided. Progressive right ventricular fibrosis, ventricular hypertrophy, and chronic hypoxia are avoided, which may reduce the incidence of late ventricular arrhythmias. However, surgical correction at a young age is associated with an increased incidence of transannular patching and consequent pulmonary regurgitation. Progressive pulmonary regurgitation is associated with late ventricular arrhythmias and sudden death. These consequences may be prevented by timely pulmonary valve replacement. Palliative procedures include an aortopulmonary shunt, balloon dilation of the right ventricular tract, and stent placement. Of these measures, the aortopulmonary shunt is preferred, as it results in a more predictable outcome. Complications associated with shunt placement include shunt occlusion, pulmonary artery distortion, and occasionally, volume overloading of the left ventricle and pulmonary circulation. Institutional and surgeon preferences exist for either surgical strategy, and ultimately are justifiable when they produce the best outcomes for the individual patient. The optimal surgical strategy has to be determined by large prospective randomized studies that compare the functional status of the pulmonary valve and the need for reoperation at long-term follow-up.